Method of bending operations and bending system using the same

ABSTRACT

A method and system are provided that enable an operator without skills in performing bending operations to easily and quickly perform precise bending operations on a sheet workpiece by following a skilled operator&#39;s experience, hints or data. The method may include: storing data for a shape of a part; storing data related to a bending order for manufacturing the part from a workpiece; selecting tools for performing each bending operation; storing data for the selected tools or dies; storing bending press control data for controlling the operation of the bending press to perform the bending operations in accordance with the bending order; and storing bending operation support information for supporting an operator for performing the bending operations by using the bending press. The bending operation support information may include hints or information regarding at least one of the following operations: attaching a protective tape on the shoulder of a die; arranging small tools on the bending press so that a punch and die are laterally shifted from each other; attaching a small die on a ram with a fixing tape; aligning a punch and die relative to each other in a longitudinal direction; determining an original point of one of the punch and die relative to each other; positioning a workpiece relative to a punch and die; positioning a workpiece relative to a backgauge device; and checking a dimension of a shape of the workpiece after performing a bending operation.

This is a continuation of application No. 08/771,308, filed Dec. 20,1996, now U.S. Pat. No. 5,799,530 the contents of which hereinincorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method of bending operations and abending system using the same, and more particularly to a method ofbending operations in a plate material such as sheet metal by using abending press such as a press brake, and a bending system using thatmethod.

2. Prior Art

When various parts or products with complicated shapes are manufacturedby performing one or more bending operations, various preparation stepshave to be carried out before the actual bending operations areperformed. Examples of such preparation steps are as follows:determining the order of bending operations along bending lines;arranging bending tools on a bending press; and adjusting the positionsof the bending tools in the bending press. In fact, conventionally,enormous working hours has been wasted to carry out these preparationsteps. Further, when a bending operation for manufacturing a specificproduct has been finished, the data concerning the preparation steps hasbeen thrown away. Thus, even when products that are the same as orsimilar to the previous product are manufactured later, the preparationsteps had to be carried out again.

SUMMARY OF THE INVENTION

The object of the present invention is to solve the foregoing problemsof the conventional method and system.

Specifically, the object of the present invention is to provide a methodand a system for bending operation in which various data concerningpreparation steps for a particular bending operation are suitably storedin a memory so that they can be used in a subsequent bending operationsfor manufacturing parts having the same shape or similar shapes.

Another object of the present invention is to provide a method or asystem by which an operator without skills in performing bendingoperations can easily and quickly perform precise bending operations ona workpiece by following skilled operator's experience, hints, or data.

To achieve the foregoing objects, according to a first aspect of theresent invention, there is provided a method of generating data formanufacturing a product or a part with a predetermined shape by using abending press that is provided with a detachable die. The methodcomprises the steps of:

entering shape data relating to the part or product;

entering a bending order for manufacturing the part or product from theworkpiece;

selecting tools for performing the bending operations in the bendingorder;

entering die data for specifying the selected tools;

entering bending press control data for controlling the operation of thepress for performing each bending operation which is performed in thebending order; and

entering bending operation support information for supporting anoperator for performing the bending operation.

The bending operation support information includes at least one of thefollowing hints or information regarding the operations of:

attaching a protective tape on the shoulder of a die;

arranging small tools on the bending press so that punch and die arelaterally shifted from each other;

attaching a small die on a ram with a fixing tape;

aligning the punch and die relative to each other in a longitudinaldirection;

determining the original point of one of the punch and die relative tothe other;

positioning the workpiece relative to the punch and die;

positioning the workpiece relative to a back gauge device; and

inspecting dimensions of a shape of the workpiece after a bendingoperation.

According to a second aspect of the present invention, there is providedanother method of manufacturing a part or a product with a predeterminedshape by using a bending press that has a detachable die. This methodcomprises the steps of:

entering shape data relating to the part or the product;

entering a bending order for manufacturing the part or the product fromthe sheet metal:

selecting tools for performing each of bending operations to beperformed in the bending order;

entering die data for specifying the selected tools;

mounting the selected die on the bending press;

entering bending press control data for controlling the operation of thebending press for performing each of the bending operations to beperformed in the bending order;

bending the sheet metal in accordance with bending press control datafor each of the bending operations; and

entering bending operation support information for supporting anoperator who is to perform bending operations to manufacture a part or aproduct that has the same shape as or a shape similar to the part or theproduct produced in the foregoing bending step.

According to a third aspect of the present invention, there is provideda still another method of manufacturing a part or a product having apredetermined shape by bending a sheet metal by a bending press. Thismethod comprises the steps of:

determining a bending order and tools for use to manufacture the part orthe product in accordance with the shape thereof;

storing the determined bending order and the tools in a computer memory;

selecting the determined tools from a die storage;

determining arrangement of the tools on the bending press;

storing the determined arrangement of the tools in the computer memory;

mounting the tools on a bending machine with the determined arrangement;

determining an attitude of insertion of the sheet metal into the bendingpress in each of the bending steps to be performed in the bending order;

storing the determined attitude of insertion of the determined sheetmetal for each of the bending steps; and

inserting the sheet metal with the insertion attitude into the bendingpress for each of the bending steps and bending the sheet metal alongpredetermined bending lines on the sheet metal by the bending press.

According to a fourth aspect of the present invention, there is provideda system for generating data for manufacturing a part by bending aworkpiece along a plurality of bending lines by a bending press that hasdetachable tools. The system comprises:

a section that stores data for a shape of the part;

a section that stores data for a bending order for manufacturing thepart from the workpiece;

a section that stores data for specifying the selected dies for eachbending operation;

a section that stores bending press control data for controlling theoperation of the press to performs the bending operations in the bendingorder; and

a section that stores bending operation support information forsupporting an operator for performing the bending operation by using thebending press.

In accordance with the present invention, various optimum steps (orprocedures) relating to the bending operations, which are carried out bya skilled operator for manufacturing a predetermined part or a product,are stored in a computer memory as operation information for each part.Therefore a non-skilled operator can learn, from the computer memory,the stored optimum operation information for each part or product laterand easily and quickly perform the optimum steps (or procedures) formanufacturing the part or the product by following the skilled operator.That is, even a non skilled operator can quickly start the bendingoperation without taking an excessively long time for standby operations(or preparation steps) for manufacturing the part or product.

The term "part" in this specification means a product that is to bedistributed in a market as well as a portion of the product.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of an embodiment of a plate bending systemaccording to the present invention;

FIG. 2 is a flow chart of the overall operation of the plate bendingsystem shown in FIG. 1;

FIG. 3 is a flow chart showing a detailed operation of a step in theflow chart shown in FIG. 2, and specifically showing the operation of astep for manufacturing a new part or product in FIG. 2;

FIG. 4 is a flow chart showing a detailed operation of a step in theflow chart shown in FIG. 3, and specifically showing the operation astep for performing an i-th bending operation on the plate tomanufacture the new part in FIG. 3;

FIG. 5 is a schematic view showing a part that is displayed on thescreen of a terminal computer in step S22 in FIG. 3;

FIG. 6A and FIG. 6B respectively are a 2D unfold view of the shape ofthe part and a view of a table that shows bending lines and tools to beused, both of the views being displayed on the screen of the terminalcomputer in step S23 shown in FIG. 3;

FIG. 7A and FIG. 7B are views showing layout of tools to be used andoperation support information relating to the layout, the views beingdisplayed on the screen of the terminal computer in step S25 and stepS26 in FIG. 3;

FIG. 8 is a cross sectional view of a die and a back gauge device thatare displayed on the screen of the computer terminal in relation to aalignment and an original-point determination operations in steps S28and s30 in FIG. 3;

FIG. 9A, FIG. 10A and FIG. 11A are schematic views showing attitudes ofa workpiece with respect to tools on a bending press and operationsupport information relating to positioning of the workpiece withrespect to the bending press, which are displayed on the screen of theterminal computer in step S44 in FIG. 4;

FIG. 9B, FIG. 10B and FIG. 11B are schematic views showing the partswith dimensions data and operation support information relating to theinspection of the dimensions, which are displayed on the screen of theterminal computer in step S48 in FIG. 4;

FIG. 9C, FIG. 10C and FIG. 11C are other schematic views showing theparts with dimension data and operation support information relating tothe inspection of the dimensions, which are displayed on the screen ofthe terminal computer in step S48 in FIG. 4.;

FIG. 12A is a flow chart showing a detailed operation of a portion ofthe operation shown in the flow chart of FIG. 2, and specifically theflow chart showing the operation when the same or a similar part ismanufactured in FIG. 2;

FIG. 12B is a flow chart showing a detailed operation of a portion ofthe operation shown in flow chart of FIG. 12A, and specifically the flowchart showing the operation for performing an i-th trial bendingoperation on a sheet metal in FIG. 12A;

FIG. 13A and FIG. 13B respectively are a perspective schematic view anda schematic cross sectional view of a bending press used in anembodiment of the plate bending system according to the presentinvention; and

FIG. 14 is an explanatory view for explaining value D, value L and valueYz in the bending press.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Examples of the present invention will now be described with referenceto the drawings.

FIG. 1 is a block diagram of a plate bending system according to thepresent invention. As shown in FIG. 1, the plate bending systemaccording to this embodiment includes a factory office 30 for receivingfrom a customer an order for manufacturing a part or a product (a bentworkpiece) with a predetermined shape and a plurality of bendingstations 20 and 22 with bending presses. The bending stations receivefrom the factory office 30 instructions to manufacture the ordered partor product.

The factory office 30 is provided with a server computer (hereinaftercalled a "server") 31 having a database 33. The database 33 in theserver 31 stores a variety of data about parts which have beenmanufactured by the bending system, as will be described later indetail. A bar-code preparation apparatus 31a for preparing bar codes isconnected to the server 31.

The first bending station 20 of the bending stations 20 and 22 has afirst bending press 21 such as a press brake and a first computerterminal (hereinafter called a "terminal for a press" or simply called a"terminal") 25. The terminal 25 includes an NC unit for controlling thefirst bending press 21.

The first bending press 21 includes, for example, a C-shape frame 35, asshown in FIGS. 13A and 13B. A plurality of punches 39 are disposed atthe lower end of an apron 37a, which is provided on an upper supportplate 37 of the C-shape frame 35, along a straight line running in thex-axis direction. Moreover, a ram 43, which is movable vertically, issupported by a lower support plate 41 of the C-shape frame 35. Aplurality of dies 45 for bending a plate (hereinafter called a"workpiece") W in cooperation with the punches 39, are disposed at thetop end of the ram 43 along a straight line running in the x-axisdirection. That is, when the workpiece is inserted between the punches39 and the dies 45 and then the ram 43 is moved upwards, the punches 39and the dies 45 are mutually engaged to one another so that theworkpiece W held therebetween is bent upward.

Again referring to FIG. 1, connected to the terminal 25 are a keyboard25c for entering data into the terminal 25, a CRT unit (hereinaftercalled a "CRT") 25b serving as a display unit for displaying datasupplied from the terminal 25 and a bar-code reading unit (bar codescanner) 25a for reading bar codes made by the bar-code preparationapparatus 31a and providing the read bar code data to the terminal 25.Here, data can be entered into the terminal 25 by using touch keysprovided on the CRT screen as well as the keyboard 25c.

Similarly to the first bending station 20, the second bending station 22is provided with a second bending press 23 and a second computerterminal 27. A keyboard 27c, a CRT 27b and a bar-code reading unit 27aare connected to the terminal 27. The server 31 of the factory office 30and the terminals 25 and 27 of the bending stations 20 and 22 areconnected through a network 29 to one another so as to allow mutual datacommunication therebetween.

Referring to FIG. 2, the overall operation of the plate bending systemwill now be described.

In step S1, various data concerning ordered part are received by thefactory office 30. Such data contains, for example, the part number ofthe ordered part and data on the shape of the part. The part number is,for example, a combination of symbols and numerals, such as "PT123a".The symbol "PT" indicates the ordered part being a part of a completeproduct, and the numeral "123" specifies the type of the part, and thesymbol "a" specifies the dimensions of the part indicated by "123". Thedata on the shape of the part consists of data for a 3D perspective viewof the ordered part, data for a 2D unfolded view of the same or data for2D, three views of the same; the 2D, three views consist of a frontview, a plan view and a side view. In step S1, such data for the orderedpart are entered into the server 31.

In step S2, the server 31 performs one or more searches on the basis ofthe entered part number to see whether bending operation data for a partthat is the same as the ordered part is stored in the database 33.

When no data on the same part is in the database 33, an operator inputsinto the server 31 the data on the shape of the ordered part in step S3.The data on the shape entered in step S3 consists of data concerning a3D perspective view of the ordered part, data concerning a 2D unfoldedview of the same or 2D three views of the same. When data on one of theviews are entered, the server 31 calculates data on two other views onthe basis of the entered data by a predetermined calculation method. Forexample, if data for the 2D three views are entered, the server 31calculates data for the 3D perspective view and 2D unfolded view.

In step S4, the server 31 carries out a search on the basis of the partnumber to see whether data for bending operations for parts similar tothe ordered part (i.e. similar parts) are stored in the database 33. Forexample, when the part number of the ordered part is "PT123a", a searchis carried out to see whether the database 33 includes data for theparts designated by part numbers "PT123b", "PT123c" and "PT123d" and thelike.

If it is detected in step S4 that the data for the similar parts isstored in the database 33, the operation proceeds to step S5, where datafor the similar parts are retrieved from the datebase 33. Moreover, instep S5, the retrieved data, data on the shape of the ordered part, andthe part number of the ordered part are stored into the database 33together with information indicating the associated data is for asimilar part. That is, in step S5 the operator stores into the database33 the retrieved data, the part number of the ordered part, data on theshape of the ordered part, and the data indicating that the retrieveddata item is data for a similar part, as a set of data.

If no part number of a similar part is detected in step S4, theoperation proceeds to step S6. In step S6, the data on the shape of theordered part and the part number of the ordered part are stored in thedatabase 33 together with data indicating that the ordered part is a newpart. That is, in step S6, the server 31 stores in the database 33 thedata indicating that the ordered part is a new part, the part number ofthe ordered part, and the shape of the ordered part as a set of data.

In step S2, if the same part number as the part number of the orderedpart is detected, the operation directly proceeds to step S7.

In step S7, the bar-code preparation apparatus 31a connected to theserver 31 prepares a bar code sheet that specifies the part number ofthe ordered part. The prepared bar code sheet is attached to anoperation instruction sheet to be delivered to bending stations 20 and22.

In step S8, it is determined whether data of all of the ordered partshas been processed. When all data have not yet been processed, theoperation returns to step S1. If the process has been completed, theoperation proceeds to step S9.

In step S9, the factory office 30 assigns and delivers the operationinstruction sheets to the bending station 20 or the bending station 22in accordance with the skill of the operator at each bending station 20,22 and with the availability of the bending stations. For example, anoperation instruction sheet for a new part is delivered to a bendingstation at which a skilled operator is working, while an operationinstruction sheet for the same or a similar part is delivered to abending station at which a low skill operator is working.

When the operation instruction sheet is received by each of the bendingstations 20 and 22, the operation proceeds to step S10. In step S10, thebar code attached to the operation instruction sheet is read by thebar-code reading unit 25a or 27a. Thus, data for the ordered partsassigned to a bending station are retrieved from the database 33 andtransmitted to either one of the terminals 25 and 27. As describedabove, when a ordered part assigned to a station is a new part, theretrieved data contains the part number of the ordered part, the shapeof the ordered part, and information indicating that the ordered part isa new part. When the ordered part assigned is the same part (which meansthat the data for the same part as the ordered part has been stored inthe database 33), the retrieved data contain the part number of theordered part and data for the same part retrieved from the data base andinformation indicating that the retrieved data is for the same part.When the ordered part assigned to a station is a similar part (whichmeans that the data for part(s) similar to the ordered part has beenstored in the database), the retrieved data contain the data for thesimilar part, the part number of the ordered part, and the shape of theordered part, information indicating that the retrieved data is data forthe similar part.

In step S11, it is determined whether the assigned part is a new part,in other words whether the bending operation is for a new part. When theassigned part is a new part, the operation proceeds to step S12. In stepS12, a new bending operation or new-part bending operation is performedas described in detail in the following with reference to FIGS. 3 and 4.On the other hand, when the ordered part is the same or a similar part,the operation proceeds to step S13, where a repeat (reiteration process)or a similar bending operation is performed as described in detail inthe following with reference to FIGS. 12A and 12B. Then, the operationproceeds to step S14, where the overall operation is completed.

Referring now to FIG. 3, the new-part bending operation performed instep S12 will be described in detail. It is supposed that the new-partbending operation is performed in the first bending station 20.

As described above, when the assigned part is a new part, the data thatthe terminal 25 retrieves in step S10 of FIG. 2 includes the part numberof the ordered part, data for the shape of the part (i.e. data of the 2Dthree views, the 3D perspective view or the 2D unfolded view) andinformation indicating that the part is a new part.

If, in step S11 of FIG. 2, it is determined that the ordered part is anew part, the operation proceeds to step S21, where a guide program fora new bending operation is activated.

In step S22, in accordance with the guide program, the shape of theordered part as well as the part number of the ordered part andinformation indicating that the ordered part is a new part are displayedon the screen of the CRT 25b. For example, a 3D perspective view 47 ofthe part with dimension lines for "600", "700" and "50" as shown in FIG.5 and/or a 2D unfolded view 49 of the part with bending lines B1, B2, B3as shown in FIG. 6A are displayed on the screen of the CRT 25b.Moreover, a bending order/tool table 51 as shown in FIG. 6B aredisplayed on the screen of the CRT unit 25b together with the views ofthe part. In FIG. 6B, when the table initially appears on the screen,the bending line column, the tool column, and the tool length column areblank (not shown in the drawings).

In step S23, the operator refers to, for example, the 3D perspectiveview 47 as shown in FIG. 5 and the 2D unfolded view as shown in FIG. 6Aand determines a bending order in which a workpiece is bent along thebending lines B1, B2 and B3. Moreover, the operator selects tools(punches and dies) for bending the workpiece along the bending lines B1,B2 and B3. The determination of the bending order is performed by, forexample, sequentially clicking the bending lines B1, B2 and B3 on the 2Dunfolded view as shown in FIG. 6A with a mouse pointer and the like. Asa result, each of the bending line numbers B1, B2, B3 are entered, inorder of bending operation, into each line of the bending line column ofthe bending order/tool table 51 as shown in FIG. 6B. For example, asshown in FIG. 6B, if the bending lines are bent in order of B3, B2 andB1, bending line B3 is entered into the first line for the bending order1, bending line B2 entered into the second line for the bending order 2and bending line B1 entered into the third line for the bending order 3.

Then, the operator determines tools for bending the workpiece along thebending lines B1, B2 and B3. Selections of the tools are performed by,for example, entering suitable die numbers into lines in the column forthe tool number in FIG. 6B. In the example shown in FIG. 6B, punch P1and die D1 are used for the bending along the bending lines B3 and B2,and punch P2 and die D2 used for the bending along the bending line B1.Thus, data of P=P1 and D=D1 are entered into each of the lines forbending lines B3 and B2, and data of P=P2 and D=D2 are entered into theline for bending line B1. For example, the data P1 and D1 indicate thepunch number 402 and the die number 30286 (11) and, the data P2 and D2indicate the punch number 14702 and the die number 30286 (10). To assistthe selection of the tools, a menu for available tools may be displayedon the screen of the CRT so that the operator can select a suitable toolfrom the menu.

Then, the lengths of the selected tools are determined and entered intothe tool length column of the table 51. For example, as the length ofpunch P1 and die D1, 835 mm is entered into the first and the secondlines of the table, while 50 mm is entered into the third line thereof,as the length of the punch P2 and die D2, as shown in FIG. 6B. Then, thebending order/die table 51 are entered into a memory of the terminal 25by suitable operation at the keyboard 25c.

In step S24, the operator selects tools (punches and dies) from a diemagazine while referring to the bending order/die table 51 on the CRTscreen 25b. Then, the operator places and mounts the selected tools onthe apron 37a and the ram 43 of the first bending press 21 by using hisexperience and skill.

In step S25, the operator enters into the terminal 25 data for thearrangement of the tools (or the layout of the tools) on the apron 37aand the ram 43. For this purpose, when a suitable key on the keyboard25c is depressed, an image as shown in FIG. 7A appears on the screen ofthe CRT 25b. Although omitted from the drawing, when the image of FIG.7A initially appears on the screen, only figures showing the apron 37sand the ram 43, central position O and a direction symbol 53 aredisplayed, while the other figures and characters are not displayed.After the foregoing screen is displayed, the operator enters symbolsand/or figures of the punch P1 and die D1 into the terminal in such amanner, for example, that the central position of each figure ispositioned away from the central position O by a distance of -500 mm, asshown in FIG. 7A.

Moreover, description, "front-side mounting" or "reverse-side mounting"may be entered for each of the punch and the die; these informationspecify whether punch P1 and die D1 are mounted with the font-sidefacing forward or the reverse side facing forward. Likewise, symbolsand/or figures showing punch P2 and die D2 are entered in such a manner,for example, that the central position of each figure is positioned awayfrom the press central position O by a distance of +500 mm. Theinformation, "front-side mounting" or "reverse-side mounting" thatindicates whether punch P2 and die D2 are mounted with the front-sidefacing forward or the reverse side facing forward may also be entered.

In step S26, after the data for the arrangement of the tools areentered, the guide program generates a question whether there areadditional hints that are useful for performing the tool set-upoperation and that are worthwhile to be recorded. If the operator thinksof such hints, he enters the same into the terminal 25 as an operationsupport information. For example, when the punch and the die are to bemounted on the bending press, it is preferable to attach a tape to theshoulder portion of the die D1, D2 so that the dies D1, D2 are notflawed when attached on the ram 43. Thus, a message 1, "Attach aprotection tape to the shoulder portion of the die" may be entered as ahint, as shown in FIG. 7A. Further, if the punch P1 and the die D1, forexample, respectively are composed of small punches P5', P6' anddiesD5', D6', it is preferable to preliminary secure the small dies D5',D6' to a rail (not shown) of the ram 43 with an adhesive tape; furtherit is preferable that the small punches P5', P6' and dies D5', D6' arearranged on the rail of the ram so as to be laterally shifted from eachother, as shown in FIG. 7B. Thus, additional hints, such as message 2,"Secure the small dies to the rail of the ram with an adhesive tape" andmessage 3, "Arrange the small punches and dies so as to be shifted fromeach other" are entered into the terminal, as shown in FIG. 7B.

In step S27, an alignment of the punch and the die in the longitudinaldirection is performed. This operation is as follows. As shown in FIG.8, the die 45 of the first bending press 21, for example, is generallymounted on the ram (or the rail of the ram) 43 so as to be movable inthe longitudinal direction (i.e. in the lateral direction in FIG. 8).Therefore, when the die 45 is initially mounted on the ram 43, theposition of a bottom portion 45a of a recess of the die 45 is normallydisplaced in the longitudinal direction from the position of the apex39a of the punch as shown in FIG. 8. As a result, before bendingoperation, the longitudinal position of the die 45 is adjusted in thelongitudinal direction so that the bottom portion 45a of the recesscoincides with the apex 39a of the punch. This operation is called thealignment of the tools in the longitudinal direction. Here, when thelengths of the punch and the die are too short to precisely align thetools, supplemental punch and die with the same shape and longerdimensions are temporarily mounted on the rail of the ram 43.

In step S28, after the alignment of the tools are performed, theoperator enters an instruction on the execution of the alignment of thetool as operation support information. Then, the guide program generatesa question whether there is hints that are useful for performing thealignment of the tool. If the operator thinks of such hints, he entersthe same into the terminal 25 as additional operation supportinformation. For example, the operator may input a hint that "When shortpunch and die are to be aligned, supplemental long punch and die withthe same shape should be used with the short ones" is entered as amessage 4, as shown in FIG. 8. The guide program may generate similarquestions in the following steps whenever useful hints relating to thosesteps are to be entered although it may not be explicitly mentionedhereinafter.

In step S29, an original-point determination operation (or anoriginal-point adjustment operation) is performed. The original-point(or a reference point) is a position of the die 45 relative to the punch39 in which position the die 45 is directly engaged to the punch 39 witha predetermined engaging force without workpiece being held between thepunch 39 and the die 45. The original-point determination operation isnecessary for the reason as follows. That is, the bending angle of aworkpiece bent by the punch and the die is generally determined by thedistance moved by the die 45 relative to the punch 39 during bendingoperation. However, during the bending operation, the side frame 35 orthe like of the bending press is deformed. Thus, the distance moved bythe die 45 from a reference point determined with no engaging forcebetween the punch and die does not corresponds to the bending angle ofthe workpiece to be bent by the punch and the die. Therefore theposition of the die 45 in the above-mentioned condition where apredetermined force acts between the punch and the die is determined asa correct original position (or a reference position) of the die 45. Itshould be noted here that the load, which is applied between the punchand the die, is selected in accordance with the length of the mounteddie. That is, if a die having a length longer than a predeterminedlength is mounted, a load of 7 tons is applied between the punch and thedie to determine the original point of the die. On the other hand, if adie shorter than a predetermined length is mounted, the load of 7 tonsmay break the punch and the die. Therefore, a 3 tons, for example, whichis smaller than the durable pressure for the punch and the die isapplied between the punch and the die to determine the original point ofthe die. In the present embodiment, it is supposed that the mounted dieis longer than the predetermined length, and the load of 7 tons isapplied between the punch and the die.

In step S30, an instruction for performing the original-pointdetermination operation (or the original-point adjustment operation) anda hint relating to the original-point determination operation areentered and stored in the memory of the terminal 25 as operation supportinformation. For example, a message 5, "When a die having a lengthshorter than x mm is mounted, set the original-point determinationoperation load to be 3 tons" is entered as shown in FIG. 8. In place ofentering the message 5, a program for performing following steps may beprovided in the terminal: First, it retrieve the tool number and thelength of the tool entered in step S23. When the tool is longer than apredetermined length, it generates a first message "Perform theoriginal-point determination with 7 tons" is generated. On the otherhand, when the die is shorter than the predetermined length, itgenerates the second message "Perform the original-point determinationwith 3 tons".

In steps S31, S32, S33 and S34, trial bending of a workpiece formanufacturing the part (or the product) as shown in FIG. 5 is performed.

For this, in step S31, a trial bending operation number i for specifyingeach of bending operations is set as 1.

In step S32, the i-th trial bending operation is performed whileoperation support information relating to the i-th bending are entered,as described in detail below.

In step S33, it is determined whether all of the trial bendingoperations have been completed. If they have not been completed, thestep number i is increased by one in step S34, and then the operationreturns to step S32. If all of the trial bending operations have beencompleted in step S33, the operation proceeds to step S35, where aplurality of workpieces are successively bent in the manner determinedby the trial bending operations in step S32. During this successivebending operations, the bending accuracy is inspected each time apredetermined number of workpieces are processed. If the operationaccuracy does not satisfy a predetermined requirement, values D and L,which is described later, are modified.

After the successive bending operation has been completed, in step S36,the operator enters an operation support information on the frequency ofchecking of the bending accuracy, which is performed in other bendingoperation, such as in the operations in steps in FIGS. 11. For example,an operation support information to inspect the accuracy for every tenworkpieces is entered.

In step S37, a variety of information and data including the operationsupport information relating to the bending operation entered in stepsS23, S24, S26, S28, S30, S32, S35 and S36 are transmitted from theterminal 25 to the server 31 together with the part number and the shapeof the part, and they are all stored in the database 33 of the server31. In step S38, the bending operation for the new part is completed.

FIG. 4 is a flow chart for showing in detail the i-th trial bendingoperation and operation of entering support information relating to thesame, which are performed in step S32 in FIG. 3.

In step S41, a memory area is reserved under a number i in a memory ofthe terminal 25. When the program of FIG. 4 is first called upon, thenumber i is set to be 1 since the i has been set to be 1 in step S31

In step S42, in order to bend a workpiece along bending line B3 (FIG.6A) through an angle of 90°, numerical control data D, L and Yz for thebending press 21 are entered into the terminal 25. As shown in FIG. 14,the data D specifies the vertical position of the die 45 relative to theoriginal position (or the reference position) H₀ determined in step S29.The data L specifies the position of a back gauge device 55 in thelongitudinal direction (i.e. in the lateral direction in FIG. 14)relative to a reference position which is, for example, the centralposition Y₀ of the die 45. The data Yz specifies the vertical positionof the back gauge device 55 relative to a reference position, which is,for example, the top end of the die 45. As described above, the data Ddetermines the bending angle of the workpiece W to be bent by thebending press 21, while the data L determines the width of the workpieceW between an edge E1 (see FIG. 9A) and the bending B3. The value Yz isused to adjust the vertical position of the back gauge device 55 duringbending operation. Specifically, the height of the back gauge device isadjusted to correspond to the height of a flange formed at the rear endof the workpiece (for example, flange W2 shown in FIG. 9B). For example,in FIG. 10A, the workpiece is inserted between the punch and die in anattitude or position that the flange W2 projects downward relative to amajor portion of the workpiece. Thus, the back gauge device 55 islocated in a vertical position lower than that as shown in FIG. 9A so asthat the flange W2 is properly brought into contact with the back gaugedevice 55.

When the data L and Yz are entered, the back gauge device 55 is moved bythe control of the terminal 25 in the vertical and longitudinaldirections to a position determined by the data.

In step S43, the workpiece W is inserted between the punch 39 and thedie 45, and the rear end thereof is brought into contact with the backgauge device 55 to position the same with respect to the punch and die.Thereafter, the first trial bending is performed on the workpiece Walong the bending line B3.

In step S44, on the basis of the trial bending operation performed instep S43, operator enters operation support information in relation tothe positioning of the workpiece W relative to the punch and die. Theseoperation support information includes hints relating to the positioningof the workpiece. Specifically, as shown in FIG. 9A, when the firsttrial bending operation is completed, a figure showing the tools P1, D1on bending press 21 and the workpiece W appears on the screen of the CRT25b in response to a completion signal from the bending press 21. Inorder to inform the operator the appearance of the figure, a soundbuzzer and the like may be provided. Thus, for example, when the soundbuzzer is activated, the operator moves to a position in front of theterminal 25. In the first bending operation, the punch P1 and the die D1on the bending press 21 are used to perform the bending operation (seeFIG. 6B). In order to save this information, the color of the figures ofthe punch P1 and D1 is changed into gray as shown in FIG. 9A. Then,information concerning positioning of the workpiece W with respect tothe punch and die is saved. For this, the figure of the workpiece W onthe CRT screen is moved translationally and rotationally to a positionin front of the punch P1 and the die D1, as shown in FIG. 9A. Thismovement of the figure of the workpiece can be carried out by using amouse (not shown) or a joystick (not shown) connected to the terminal25. As described before, in the first bending operation, the edge a E1of the workpiece W is brought into contact with the back gauge device55, and the bending operation is performed along the bending line B3.Therefore, the figure of the workpiece W is located in a attitude asshown in FIG. 9A with respect to the figure of the punch P1 and die D1.

Then, as shown in FIG. 9A, the operator enters the messages 6 and 7relating to the positioning of the workpiece W as hints. Specifically,the message 6, "Insert the workpiece between the punch and die in amanner that its sheet surface faces upwards" is a hint for specifyingthe side of the workpiece W to be inserted between the tool. The "sheetsurface" means a surface of the workpiece on which a vinyl sheet isattached; the vinyl sheet is attached on that surface to protect thatsurface from being scratched during transportation. The side of theworkpiece can also be designated by specifying the directions of burrsformed on the workpiece. In this case, a message, for example, "Locatethe workpiece in such a manner that the direction of burrs facedownward" is entered. The message 7, "Securely bring the workpiece intocontact with right and left back gauge devices" is a hint for remindingthe operator to securely engaging the rear end of the workpiece with theright and left back gauge devices 55 when the workpiece W is insertedbetween the punch and die. This message 7 is entered because a precisebending cannot be achieved if either one of the back gauge devices failsto contact the rear end of the workpiece. After these information aredisplayed on the CRT 25b, all data are stored in a memory of theterminal 25.

In step S45, the operator determines in accordance with the result ofthe trial bending operation whether buckling of the workpiece hasoccurred during first trial bending operation or whether the buckling ofthe workpiece could occur during the first bending operation during thesuccessive bending operation in step S35. If an affirmativedetermination is made, the operation proceeds to step S46.

In step S46, the operator enters an instruction to support the end ofthe workpiece W from a lower position during the bending operation as aoperation support information (see message 6 a shown in FIG. 9A).

In step S47, the part manufactured by the trial bending operation isinspected. Specifically, the operator measures the length and angle of aflange W2 formed by the first bending operation.

After the measurement has been carried out, in step S48, the operatorenters into the terminal an instruction or a hint for specifyingdimensions and angles to be measured and together with their tolerances,as operation support information. Specifically, as shown in FIG. 9B,when the shape of the workpiece W including the flange W2 formed by thetrial bending operation is displayed on the screen of the CRT 25c, theoperator enters symbols relating the length "L1" of the flange W2 andsymbols relating the angle "74 1" of the same as an operation supportinformation. Moreover, a message 8 "Check that height L1 is 15 mm (±0.1mm)" and a message 9 "Check that angle θ 1 is 90°" are entered. Theshape of the flange W2 may be displayed in the form of a cross sectionalview, as shown in FIG. 9C. By displaying the shape of the flange withthe cross sectional view, the height L1 of the flange being a dimensionincluding the thickness of bottom surface portion W1 of the workpiece Wcan be more easily understood. In order to emphasize that the dimensionL1 includes the thickness of the bottom surface portion W1, a message"Note that the dimension L1 includes the thickness of the bottom surfaceportion W1" may be added to the display in FIG. 9B or 9C.

After entering the instruction or hint for measuring the height L1 andthe angle θ 1 of the flange, in step S49, the operator determineswhether the dimension L1 and the angle θ 1 are within a requiredtolerance. For example, it is determined whether the dimension L1 iswithin a range of 15 mm±0.1 mm. If it is determined in step S49 that thedimension L1 is not within the range, either or both of the values D andL are modified in step S50. Then, the operation returns to step S43 sothat the trial bending operation is again performed.

If the dimension L1 and the angle θ 1 are within the required range instep S49, the foregoing data D, L and Yz are stored in step S51 in thememory area under the number i.

Trial bending operations for the process number i=2 and for the processnumber i=3 are performed in a manner similar to the trial operation forthe process number i=1.

Specifically, when the process number i=2, in step S44, the figure ofthe workpiece W that has been bent along the bending line B3 isdisplayed on the screen of the CRT 25c together with the bending press21, as shown in FIG. 10A. In the second trial bending operation, thepunch P1 and the die D1 are again used to perform the bending operationalong the bending line B2. Therefore, the figures of the punch P1 andthe die D1 are displayed in gray, as shown in FIG. 10A. The back gaugedevice 55 is brought into contact with the flange W2 formed in the firstbending operation. Therefore, as shown in FIG. 10A, the figure of theback gauge device 55 is moved to a position lower than that of the backgauge device 55 in FIG. 9A. Then, the figure of the workpiece W issuitably moved until it has an attitude (or an orientation) that theedge E2 faces toward the punch P1 and the die D1, as shown in FIG. 10A.In the second trial bending operation, the workpiece W is bent along thebending line B2 in a direction opposite to that in the first bendingoperation. Therefore, a message 10, "Insert the workpiece W in such amanner that the sheet surface faces downwards" is entered.

In step S48 in the second trial bending operation, the shape of theworkpiece including the flange W2 formed in the first trial bendingoperation and the flange W3 formed in the second trial bending operationis displayed, as shown in FIG. 10B. Therefore, the operator inputsfigures or symbols relating the dimension L2 and the angle θ 2, whichmust be measured in relation to the flange W3, as shown in FIG. 10B.Moreover, messages 11 and 12 to measure the dimension L2 and the angle θ2 are entered. The shape of the workpiece including the figures orsymbols relating the dimension L2 and the angle θ 2 may be displayed inthe form of a cross sectional view, as shown in FIG. 10C. This viewclearly shows that the dimension L2 includes the thickness of the flangeW2 and the base portion W1.

In case of the process number i=3, in step S44, the shape of theworkpiece W that has been subjected to the first and second bendingoperations is displayed together with the punches and dies of the press21 on the screen of the CRT 25c, as shown in FIG. 11A. In the thirdtrial bending operation, the punch P2 and the die D2 are used for thebending operation. Therefore, the punch P2 and the die D2 are displayedin gray. Moreover, the figure showing the back gauge device 55 is movedto positions around the punch P2 and the die D2. Then, the operatormoves the figure showing the workpiece W until the end E3 faces thepunch P2 and the die D2, as shown in FIG. 11A. In the third bendingoperation, the workpiece W is bent along the bending line B1 in the samedirection as that in the first bending operation. Therefore, a message13 instructing this, that is, "Insert the workpiece W in such a mannerthat the sheet surface faces upwards" is entered.

In step S48 in the third trial bending operation, the shape of theworkpiece W that has the flange W2 formed in the first bendingoperation, the flange W3 formed in the second bending operation and theflange W4 formed in the third bending operation is displayed, as shownin FIG. 11B or FIG. 11C. Then, the operator inputs symbols relating towidth L3 and angle θ 3 relating to the flange W4 formed in the thirdtrial bending operation and messages 14 and 15 to measure thesedimensions.

As described above, in the new bending method according to thisembodiment, a skilled operator stores into the terminal computer 25 theoperation information for efficiently performing a trial bendingoperation in the part, as operation support information or guideinformation or hints, while performing the trial bending operations.Moreover, the operation information is transmitted to and stored in thedata base 33 of the server 31. Therefore, if the same or similar part isordered later, the operation information stored for each part isretrieved from the data base 33 so that an optimum operation formanufacturing the ordered part is performed easily and quickly. Inparticular, even an operator without skill can perform a necessarybending operation easily and quickly by referring to the operationinformation above.

Further, in the foregoing method, a guide program for guiding a newbending operation is activated (see step S21) when an operator enterinto the terminal 25 an instruction for the novel bending operation.According to the guide program for a novel bending operation, theterminal 25 urges the operator to enter suitable information includingoperation support information relating to set-up operation (preparationoperation) and the bending operation after the operator has completedactual set-up operation and bending operation. Therefore, the operatorcan securely enter suitable information including the operation supportinformation.

As described above, in step S37, the variety of the information thatrelates to the bending operation for the new part and are entered insteps S23, S25, S26, S28, S30, S32 (including steps S42, S44, S46, S48,S50 and S51) and step S36 are stored in the database 33 of the server 31together with the part number and the shape of the part. The followingTables 1 to 5 show a manner in which the foregoing various informationincluding the operation support information are stored in the database33.

First, a part file specified by a part identifying data (refereed tohereinafter as "part ID") such as the part number for specifying a partis provided. As shown in Table 1, the part file has a file for shape, afile for set-up operation and a file for bending operation. The file forthe shape stores data for the shape as shown in FIGS. 5 and 6A.

                  TABLE 1                                                         ______________________________________                                        Part ID                                                                       Part File                                                                     ______________________________________                                        File for Shape        FIGS. 5 and 6A                                          File for Set-up Operation                                                                              Table 2                                              File for Bending Operation                                                                            Table 5                                               ______________________________________                                    

The file for the set-up operation has a file for the bending order, afile for the tools, a file for the tool layout, a file for the alignmentof the tools and a file for the original-point determination operation,as shown in Table 2. Here, the file for the bending order stores bendingorder data shown in FIG. 6B or Table 3, the file for the tool or diestores data of the dies shown in FIG. 6B or Table 4, the file for thetool or die layout stores data for the layout of the die shown in FIG.7A and FIG. 7B, the file for the alignment of tools stores data for thetools shown in FIG. 8 and the message 4 therein, and the file for theoriginal-point determination operation stores data for FIG. 8 and themessage 5 therein.

                  TABLE 2                                                         ______________________________________                                        File for Set-up Operation                                                     ______________________________________                                        File for Bending Order                                                                            FIG. 6B, Table 3                                          File for Tools                    Table 4                                     File for Tool Layout                                                                                      FIG. 7A, Fig. 7B                                  File for Tool Alignment                                                                                FIG. 8 and Message 4                                 File for Original-Point                                                                                FIG. 8 and Message 5                                 Determination Operation                                                       ______________________________________                                    

                  TABLE 3                                                         ______________________________________                                        A Portion of File for Bending Order                                           Bending Line        Bending Order                                             ______________________________________                                        B1                  3                                                         B2                             2                                              B3                             1                                              ______________________________________                                    

                  TABLE 4                                                         ______________________________________                                        File for Tools                                                                               Punch Number Punch Length                                      Bending Line Number                                                                            Die Number            Die Length                             ______________________________________                                        B1             P2=14702     50                                                                              50    D2=30286(10)                              B2                                  8352                                                                    835   D1=30286(11)                              B3                                  8352                                                                    835   D1=30286(11)                              ______________________________________                                    

The file for the bending operation stores bending operation data asshown in Table 5. That is, data for symbols and figures as shown in FIG.9A and FIG. 9B (or FIG. 9C) and data of D1, L1 and Yz1 for the D, L andYz as shown in FIG. 14 are stored in relation to the bending line numberB1. In relation to the bending line number B2, data for symbols andfigures as shown in FIG. 10A and FIG. 10B (or FIG. 10C) and data of D2,L2 and Yz2 for the D, L and Yz are stored. In relation to the bendingline number B3, data for the symbols and figures as shown in FIG. 11Aand FIG. 11B (or FIG. 11C) and data of D3, L3 and Yz3 for the D, L andYz are stored.

                  TABLE 5                                                         ______________________________________                                        File for Bending Operation                                                    Bending Line                                                                           Bending Operation Support                                            Number           Information      Data for D, L, Yz                           ______________________________________                                        B1       FIGS. 9A and 9B (or FIG. 9C)                                                                      D=D1                                                                                                          L=L1                                                                          Yz=Yzl           B2                   FIGS. 10A and 10B (or FIG. 10C)                                                        D=D2                                                                                                         L=L2                                                                          Yz=Yz2           B3                   FIGS. 11A and 11B (or FIG. 11C)                                                        D=D3                                                                                                         L=L3             ______________________________________                                                                     Yz=Yz3                                       

A method of manufacturing parts by using data for bending operationstored in the database 33 will now be described with reference to FIG. 2and FIGS. 12A and 12B. Hereinafter this operation is called arepeat/similar bending operation or a same part/similar part bendingoperation. Note that FIG. 12A is a detailed flow chart of step S13 shownin FIG. 2, and FIG. 12B is a detailed flow chart of step S72 shown inFIG. 12A. The repeat/similar bending operation is supposed to beperformed at the second bending station 22 in FIG. 1.

Referring again to FIG. 2, in step S10, an operator at the secondbending station 22 reads the bar code attached to an operationinstruction sheet by using the bar code scanner 27a. Then, bendingoperation data for manufacturing a ordered part, which is the same as orsimilar to the part stored in the database 33 of the server 31, isretrieved to the terminal 27.

In step S11, if it is determined that the ordered part is not a new part(that is, if the database 33 includes bending operation data for one ormore parts that are the same as or similar to the ordered part), theoperation proceeds to step S61 in FIG. 12A. In step S61, a guide programfor guiding the operator in performing the repeat/similar bendingoperation is activated.

In step S62, a perspective view of the ordered part and that of a partthat is the same as or similar to the ordered part are retrieved anddisplayed on the CRT screen 27b as shown in FIG. 5; here, a statementthat the ordered part is the same as or similar to the part or partsdata of which have been stored in the database 33 is simultaneouslydisplayed on the CRT screen 27b (not shown). When bending data for asimilar part is used to manufacture the ordered part, the shape of theordered part and the shape of the similar part are also simultaneouslydisplayed on the CRT screen 27b. Here, in the following, it is supposedthat the shapes of the ordered part and of the similar part differs fromeach other slightly, for example, in width of the flange W2 as shown inFIG. 5. Then, the operator observes the perspective views of the partsto confirm the shape of the part to manufacture.

In step S63, the operator depresses an suitable key on the keyboard 27cso that data for unfolded views of the ordered part (and that of thesimilar part), data for the bending order for manufacturing the part anddata for the tool numbers to be used are retrieved and displayed on thescreen, as shown in FIGS. 6A and 6B. Thus, the operator can easilyconfirm the unfolded views of the parts, the bending order and the dieto be used.

In step S64, the operator selects necessary tools (i.e. punches anddies) P1, D1, P2 or D2 from an suitable die magazine by referring to thetools displayed on the screen 27b.

In step S65, the operator again depresses an suitable key on thekeyboard 27c so that the layout (arrangement) of the tools on the secondbending press 23 and hints for arranging the tools are displayed on thescreen as operation support information, as shown in FIG. 7A and FIG.7B.

In step S66, the operator places or mounts selected tools on the bendingpress 23 by referring to the tool arrangement displayed on the CRTscreen 27b in step S65.

In step S67, the operator depresses an suitable key on the keyboard sothat the cross sectional shape of the tools, the instructions (notshown) for performing the alignment of the tools and the hints oroperation support information relating to the alignment of the tools(such as the message 4) are displayed on the screen 27b, as shown inFIG. 8.

In step S68, the operator aligns the tools on the bending press 23 byreferring to the figures and statements displayed on the screen 27b.

In step S69, the operator again depresses an suitable key on thekeyboard 25c so that the cross sectional view of the tools, theinstruction (not shown) for determining the original point of the dieand hints for performing original-point determination (such as themessage 5) are displayed on the screen, as shown in FIG. 8.

In step S70, the operator performs the determination of theoriginal-point of the die in the bending press 23 while referring toinformation displayed on the screen 27b in step S69.

When the original-point determination operation is completed, theprocess proceeds to step S71, where the bending operation number i isset to 1.

In step S72, the operator performs an i-th trial bending operation in aworkpiece referring to operation support information for the i-th trialbending operation displayed on the screen of the CRT 27b.

In step S73, it is determined whether all of the trial bendingoperations have been completed. If all of the trial bending operationshave not been completed, the bending operation number i is increased byone at step S74, and the process returns to step S72.

If all of the trial bending operations have been completed in step S73,the operation proceeds to step S75.

In step S75, the frequency for checking the accuracy of the bendingoperations carried out during successive bending operation performed instep s76 is displayed on the screen. For example, an instruction tocheck the accuracy for every 10 workpieces is displayed on the screen ofthe CRT 27b.

In step S76, the operator successively bends a plurality of workpiecesin accordance with the trial bending operations performed in step S72 soas to manufacture the plurality of the ordered parts. During thisoperation, the operator follows the instructions displayed in step S75to check the bending accuracy each time 10 parts are processed. If theprocessing accuracy does not satisfy a predetermined tolerance, thevalue L and value D are modified.

In step S77, the value L and the value D modified in step S76 are storedin the database 33 through the terminal 27. In step S78, therepeat/similar being process is completed.

FIG. 12B is a flow chart showing details of the i-th trial bendingoperation performed in step S72 shown in FIG. 12A.

When the operator sets the bending operation number i to 1 in step S71,the process proceeds to step S80, where information for positioning theworkpiece W relative to the tools P1 and D1 and the hints relating tothe operation for locating the workpiece are displayed as operationsupport information on the screen of the CRT 27b, as shown in FIG. 9A.

In step S81, the operator locates the workpiece W with respect to thepunch P1 and the die D1 by referring to the display on the screen.Moreover, the workpiece W is located so that the bending line B3 of theworkpiece W is positioned between the punch P1 and the die D2. Here, theposition of the back gauge device 55 is located to a predeterminedheight in the rear of the punch P1 and the die D1 in accordance with thedata of L and Yz retrieved from the database 33.

When the ordered part has a shape similar to that of the part retrievedfrom the database 33, the position of the back gauge device 55 in thelongitudinal direction (that is, the value of L) is somewhat modified instep S81 in accordance with the actual width of the flange W2 of theordered part (as described above, it is supposed here that the length ofthe flange W2 of the ordered part is somewhat different from the lengthof the flange W2 of the similar part stored in the database 33).

In step S82, the operator executes the ith trial bending operation onthe workpiece W along the bending line B3.

After the bending operation has been completed, in step S83, the shapeof the workpiece formed with the flange W2 as well as the figures (andinstructions) relating to the dimension L1 and angle θ 1 to be measuredfor inspection of the bending accuracy are displayed on the screen ofthe CRT 27b, as shown in FIG. 9B or 9C.

In step S84, the operator inspects or measures the dimension L1 and theangle θ 1 of the workpiece by referring to the dimension and the angledisplayed on the screen.

In step S85, it is determined whether the dimension L1 and the angle θ 1are within a predetermined tolerance. If the predetermined tolerance isnot satisfied, the value D and the value L are modified in step S86 andin step S87, the i-th trial bending operation is completed.

In the second trial bending operation where i=2, the figures and symbolsshown in FIG. 10A are displayed in step S80, and in step S83, figuresand symbols shown in FIG. 10B or FIG. 10C are displayed.

Likewise, in the third bending operation where i=3, figures and symbolsshown in FIG. 11A are displayed in step S80, and in step S83, figuresand symbols shown in FIG. 11B or FIG. 11C are displayed.

As described above, in the repeat/similar bending operation according tothis embodiment, variety of data including operation support informationstored for manufacturing one of more parts that are the same as orsimilar to the ordered part are retrieved from the data base; then thebending operation is performed on the basis of the retrieved dataTherefore, an operator without skill at bending operation can completelyuse the operation information stored by a skilled operator. As a result,even the non-skilled operator can easily and quickly perform a precisebending operation;

What is claimed is:
 1. A method of preparing data for manufacturing aproduct or a part with a predetermined shape by using a bending pressprovided with detachable tools, said method comprising entering bendingoperation support information, into a computer memory, aftersuccessfully completing bending operations, in order to support anoperator later performing bending operations on a workpiece tomanufacture said product or part, said bending operation supportinformation being specific to the completed bending operations.
 2. Themethod of claim 1, said method further comprising:entering shape datarelating to said part or product; entering a bending order formanufacturing said part or product from said workpiece; and enteringtool data for specifying tools for performing said bending operations tomanufacture said part or product.
 3. The method of claim 2, said methodfurther comprising entering bending press control data for controllingsaid bending press to perform said bending operations in said bendingorder.
 4. The method of claim 2, said method furthercomprising:performing an alignment of said tools in a longitudinaldirection of said bending press before performing said bendingoperations; and storing support information regarding an execution ofthe alignment of said tools in the longitudinal direction.
 5. The methodof claim 2, said method further comprising:performing an original-pointadjustment operation to adjust an original point of a die with respectto a punch; and storing supporting information regarding an execution ofthe original-point adjustment operation.
 6. The method of claim 2, saidmethod further comprising:performing a trial bending operation for eachof said bending operations to be performed on said workpiece; andstoring support information regarding a frequency of checking anaccuracy of dimensions of said workpiece.
 7. The method of claim 2, saidmethod further comprising:performing an original-point adjustmentoperation to determine an original point of a die with respect to apunch; and storing control data D, L and Yz for performing said bendingoperations with said bending press, wherein D specifies a verticalposition of the die relative to the original point of the die, Lspecifies a position of a backgauge device in a lateral directionrelative to a central position of the die, and Yz specifies a verticalposition of the backgauge device relative to a top end position of thedie.
 8. The method of claim 1, said method further comprising:performingan alignment of tools in a longitudinal direction of said bending pressbefore performing said bending operation; and storing supportinformation regarding an execution of the alignment of tools in thelongitudinal direction.
 9. The method of claim 1, said method furthercomprising:performing an original-point adjustment operation to adjustan original point of a die with respect to a punch; and storing supportinformation regarding an execution of the original-point adjustmentoperation.
 10. The method of claim 1, said method furthercomprising:performing a trial bending operation for each of said bendingoperations to be performed on said workpiece; and storing supportinformation regarding a frequency of checking an accuracy of dimensionsof said workpiece.
 11. The method of claim 1, said method furthercomprising:performing an original-point adjustment operation todetermine an original point of a die with respect to a punch; andstoring control data D, L and Yz for performing said bending operationswith said bending press, wherein D specifies a vertical position of thedie relative to the original point of the die, L specifies a position ofa backgauge device in a lateral direction relative to a central positionof the die, and Yz specifies a vertical position of the backgauge devicerelative to a top end position of the die.
 12. A method of generatingdata for manufacturing a part by bending a workpiece along a pluralityof bending lines with a bending press that includes detachable tools,said method comprising:storing data for a shape of said part in acomputer memory; storing data indicating an order of bending operationsin which the workpiece is bent along the bending lines in the computermemory; selecting tools for performing each of said bending operationsalong the bending lines; storing data for the selected tools in thecomputer memory; storing bending press control data in the computermemory for controlling said bending press to perform said bendingoperations in said bending order; and storing bending operation supportinformation in the computer memory, after successfully completingbending operations, to support an operator later performing said bendingoperations with the bending press, wherein said storing of said bendingoperation support information comprises storing support informationregarding operation of at least one of the following: attachingprotective tape on a shoulder of a die; arranging small tools on saidbending press so that a punch and a die are laterally shifted from eachother; attaching a small die on a ram with fixing tape; aligning a punchand a die relative to each other in a longitudinal direction;determining an original point of a punch or a die relative to the other;positioning said workpiece relative to a punch and a die; positioningsaid workpiece relative to a backgauge device; and inspecting dimensionsof a shape of said workpiece after performing one of said bendingoperations.
 13. A method of manufacturing a part by bending a workpiecealong a plurality of bending lines with a bending press that includes adetachable tool, said method comprising:storing data for a shape of saidpart in a computer memory; storing data in the computer memoryindicating a bending order for manufacturing said part from saidworkpiece; selecting tools for performing each of said bendingoperations in said bending order; storing data for specifying theselected tools in the computer memory; mounting said selected tools onsaid bending press; storing bending press control data in the computermemory for controlling said bending press to perform each of saidbending operations; bending said workpiece in said bending order inaccordance with the bending press control data for each of said bendingoperations; and thereafter storing bending operation support informationin the computer memory to support an operator later performing bendingoperations, wherein said storing of said bending operation supportinformation comprises storing support information regarding operation ofat least one of the following: attaching protective tape on a shoulderof a die; arranging small tools on said bending press so that punch anda die are laterally shifted from each other; attaching a small die on aram with fixing tape; aligning a punch and a die relative to each otherin a longitudinal direction; determining an original point of a punch ora die relative to the other; positioning said workpiece relative to apunch and a die; positioning said workpiece relative to a backgaugedevice; and checking a dimension of a shape of said workpiece afterperforming one of said bending operations.
 14. A method of manufacturinga part by bending a workpiece along a plurality of bending lines with abending system, said method comprising:determining a bending order andtools to manufacture said part in accordance with a shape of said part;storing the determined bending order and the tools in a computer memory;selecting the determined tools from a tool storage; determining anarrangement of the tools on said bending press; storing the determinedarrangement of said tools in the computer memory; mounting said tools onsaid bending press in accordance with said determined arrangement;determining an attitude of the workpiece to be fed into said bendingpress at each bending step; storing the determined attitude of theworkpiece for each bending step in a computer memory; and feeding theworkpiece into said bending press with said attitude for each bendingstep and bending the workpiece along the bending lines with said bendingpress.
 15. A system for generating data for manufacturing a part bybending a workpiece along a plurality of bending lines with a bendingpress that has detachable tools, the system including a computer memory,the system comprising:a memory section that stores data relating to ashape of said part; a memory section that stores data indicating abending order for manufacturing said part from said workpiece; a memorysection that stores data for specifying the selected dies for eachbending operation; a memory section that stores bending press controldata for controlling said bending press to perform each bendingoperations in said bending order; and a memory section that storesbending operation support information for supporting an operator toperform each bending operation by using said bending press, wherein saidstoring of said bending operation support information occurs aftersuccessfully completing bending operations and comprises storing supportinformation regarding the operation of at least one of the following:attaching protective tape on a shoulder of a die; arranging small toolson said bending press so that a punch and a die are laterally shiftedfrom each other; attaching a small die on a ram with fixing tape;aligning a punch and a die relative to each other in a longitudinaldirection; determining an original point of a punch and a die relativeto the other; positioning said workpiece relative to a punch and a die;positioning said workpiece relative to a backgauge device; and checkinga dimension of a shape of said workpiece after performing a bendingoperation.
 16. A system for generating data for manufacturing a part,said system comprising:a server provided with a database for storingvarious data relating to completed bending operations for manufacturinga part, and a bar code generator for generating a bar code in relationto the part to be produced by said bending press; and a terminalcomputer for controlling said bending press, said terminal computerbeing connected to said server to support data communications with saidserver, said terminal computer comprising a bar code reader for readinga bar code and retrieving data concerning the part from said database ofsaid server.
 17. The system of claim 16, further comprising a memorysection that stores support information regarding execution of anoriginal-point adjustment operation performed to adjust an originalpoint of a die with respect to a punch.
 18. The system of claim 16,further comprising a memory section that stores support informationregarding a frequency of checking an accuracy of dimensions of saidworkpiece.
 19. The system of claim 16, flyer comprising a memory sectionthat stores control data D, L and Yz for performing said bendingoperations with said bending press, wherein D specifies a verticalposition of a die relative to an original point of the die, L specifiesa position of a backgauge device in a lateral direction relative to acentral position of the die, and Yz specifies a vertical position of thebackgauge device relative to a top end position of the die.
 20. A methodfor generating data for manufacturing a part by bending a workpiece witha bending press, said method comprising:storing data that specifies ashape of said part in a computer memory; storing data indicating anorder of performing bending operations on said workpiece with saidbending press in the computer memory; storing data that specifies toolsfor performing each of said bending operations in the computer memory,said tools comprising a punch and a die; performing an original-pointadjustment operation to adjust an original point of the die with respectto the punch, and storing bending operation support informationregarding an execution of the original-point adjustment operation in thecomputer memory after successfully executing the original-pointadjustment operation; and performing a trial bending operation for eachof said bending operations to be performed on said workpiece, andstoring bending operation support information regarding a frequency ofchecking an accuracy of dimensions of said workpiece in the computermemory after successfully executing the trial bending operation.
 21. Themethod of claim 20, further comprising storing control data D, L and Yzfor performing said bending operations with said bending press in thecomputer memory, wherein D specifies a vertical position of the dierelative to the original point of the die, L specifies a position of abackgauge device in a lateral direction relative to a central positionof the die, and Yz specifies a vertical position of the backgauge devicerelative to a top end position of the die.
 22. The method of claim 21,further comprising storing bending operation support information thatspecifies dimensions of said workpiece to be checked for accuracy in thecomputer memory, and modifying the control data D and L, during a trialbending operation, when the dimensions of said workpiece are checked anddetermined not to be within a predetermined tolerance.
 23. A method forgenerating data for manufacturing a part by bending a workpiece with abending press, said method comprising:storing data that specifies ashape of said part in a computer memory; storing data indicating anorder for performing bending operations on said workpiece with saidbending press in the computer memory; storing data that specifies toolsfor performing each of said bending operations in the computer memory,said tools comprising a punch and a die; determining an arrangement ofsaid tools on said bending press; mounting said tools on said bendingpress in accordance with said determined arrangement; performing anoriginal-point adjustment operation to adjust an original point of thedie with respect to the punch, and storing bending operation supportinformation regarding an execution of the original-point adjustmentoperation in the computer memory; performing a trial bending operationfor each of the bending operations to be performed on said workpiece;and storing control data D, L and Yz for performing the bendingoperations with said bending press in the computer memory, wherein Dspecifies a vertical position of the die relative to the original pointof the die, L specifies a position of a backgauge device in a lateraldirection relative to a central position of the die, and Yz specifies avertical position of the backgauge device relative to a top end positionof the die.
 24. The method of claim 23, further comprising:storingbending operation support information regarding a frequency of checkingan accuracy of dimensions of said workpiece in a computer memory;storing bending operation support information that specifies dimensionsof said workpiece to be checked for accuracy in the computer memory; andmodifying the control data D and L, during a trial bending operation,when the dimensions of said workpiece are checked and determined not tobe within a predetermined tolerance.